Timeline

Review the timeline for the development of the A-F grading system.

"Given a probable error of around 5 in a 100-point scale, Starch (1913) recommended the use of a 9-point scale (i.e., A+, A−, B+, B−, C+, C-, D+, D−, and F) and later tested the improvement in reliability gained by moving to a 5-point scale based on the normal distribution (Starch, 1915). His and other studies contributed to the movement in the early 20th century away from a 100-point scale. The ABCDF letter grade scale became more common and remains the most prevalent grading scale in schools in the United States today" (Brookhart, et al, 2016, p. 820).